It is known to operatively couple together pipes or conduits which carry combustion exhausts away from an internal combustion engine such as in an automobile environment. Typical would be the use of a coupling to couple an outlet end of an exhaust manifold to an exhaust pipe, for example.
In the past, such couplings have been designed in an effort to compensate for thermal influences of the system, motion (such as bending or torsion), noise, vibration and harshness (“NVH”) and other parameters. In the past, such couplings have including a metallic bellows applied around the coupled joint.
The disadvantage of certain prior devices is they require a metal bellows to achieve a gas tight or semi-gas tight performance, and to resist the heat inherent in an exhaust system. The metal bellows has limited motion capabilities and increases the overall length and weight of the product to achieve the necessary motion compensation, in particular, bending and torsion. The metal bellows is not able to accept high torsion environments and must resist the torsion when the torsion would create deformation of the bellows. This adds cost and/or weight to the bellows and transfers the torsion strains downstream into the exhaust system for other portions of the exhaust system to compensate for them.
Also, the disadvantage of the prior device is that metal bellows are very expensive and must use high nickel alloys in the stainless steel material to achieve the desired performance.